Pressure-sensitive adhesives are employed in building materials. For example, as disclosed in Statutory Invention Record H1,735, roofing membranes, such as EPDM membranes, can be adhered to adjoining membranes or to a roof surface by an adhesive layer that is coated on the underside of the roofing membrane. The adhesive layer disclosed in this Invention Record includes a hydrogenated styrene-butadiene-styrene or hydrogenated styrene-isoprene-styrene block copolymer having a polystyrene content of from 20 to 40 percent by weight and an overall weight average molecular weight from 50,000 to 150,000, a polyphenylene ether resin having an intrinsic viscosity of less than 0.35 deciliters per gram or a high-softening point end-block reinforcing resin, and a tackifying resin.
Similarly, U.S. Publication No. 2003/0219564 discloses a single-ply roofing membranes that include a water impermeable membrane, such as an EPDM membrane, and a pressure-sensitive, hot-melt adhesive adhered to one side of the membrane. A release liner may be secured to the pressure-sensitive, hot-melt adhesive opposite of the water impermeable membrane.
There is a desire to improve the flame and fire resistance of building materials such as roofing membranes.